This study was conducted to assess the content of trans and saturated fats and their relationship of cookie products on Taiwan market. Also, a comparison of them from 2010 to 2018 was shown. A sampling of total 177 imported and domestic cookie products was investigated from chained convenient stores and supermarkets in New Taipei City, Taiwan on August, 2018. The fat content information was obtained from Nutrition Facts label on product. According to the regulation of Taiwan, it can be labelled as zero when the percentage of trans fat in product does not exceed 0.3%. However, the items of trans fat content in the product exceed 0.3% are 13 out of 95 and 2 out of 82 of imported and domestic products, respectively in 2018. The imported and domestic cookie products with item ratios of trans fat content exceed 0.3 % of product were 31, 45 and 5, 0 and 14, 2 percent in 2010 and 2015 and 2018, respectively. The highest trans fat contents in imported and domestic cookie product were 5.8, 3.8 and 1.3, 0 and 4, 0.4 grams per 100 grams in 2010 and 2015 and 2018, respectively. Inverse correlation of the trans fat in total fat and the saturated fat in total fat was only found in domestic cookie products in 2010 (r =-0.54, p < 0.01). Overall, the declined trend of trans fat content in domestic cookie products from 2010 to 2018 were observed. It seem corresponds to the "Regulations on Nutrition Labelling for Pre-packaged Food Products" in 2007, the revision of definition of trans fat in 2015, and the "Ban on the Use of Partially Hydrogenated Oils" in 2018. The increase of trans fat in imported cookies, including item ratio and highest content, in 2018 should be noticed. Health-conscious consumers need to pay more attentions to trans fat content on Nutrition Facts label and the country of origin of imported cookie products on Taiwan market.